This application is continuation of application Ser. No. 09/710,671 filed Nov. 9, 2000 now abandoned, and claims the benefit of the disclosures and filing date of design patent applications Ser. Nos. 29/122,732, 29/122,755, 29/122,756, and 29/122,757 all filed May 2, 2000.
In a double hung window assembly constructed from extrusions of rigid plastics material such as rigid polyvinylchloride, and of the general type disclosed in U.S. Pat. No. 4,941,288 which issued to the assignee of the present invention, it is desirable for the fabricated rectangular window frame to be designed and constructed so that the frame has upper and lower welded mitered corner joints to provide the frame with substantial strength. It is also desirable for the window frame to have uniform exterior and interior appearances around the head and jamb members of the frame and to be fabricated with minimum or no notching at the corners and with only 45xc2x0 miter cuts on the ends of each extrusion in order to simplify the fabrication of the window assembly. It is further desirable for the window frame to have sill, head and jamb members each formed from a single plastic extrusion and with the minimum weight of plastics material in each member and with maximum strength so that the fabricated window frame has a maximum strength/weight ratio.
The present invention is directed to an improved frame for a double hung window assembly and having a pair of vertical jamb members connected by a horizontal sill member and a horizontal head member and which provides all of the desirable advantages mentioned above. Each of the members is formed from a one-piece extrusion of rigid plastics material, with the jamb members both formed from the same extrusion. The head member and each of the jamb members are constructed to provide welded mitered upper corner joints without notching and with the welds at the mitered corners providing substantial joint strength. The one-piece head member also provides substantial savings in plastics material and has the same exterior appearance and the same interior appearance as the jamb members, thereby providing the window frame with a uniform appearance along jamb and head members.
Other features and advantages of the invention will be apparent from the following description, the accompanying drawings and the appended claims.